Stent delivery catheter with balloon control bands

ABSTRACT

A stent delivery catheter including a catheter tubing defining a lumen therethrough, a balloon disposed near a distal end of the catheter tubing and moving between deflated and inflated states, and proximal and distal balloon control bands concentrically arranged around respective proximal and distal end portions of the balloon. The proximal balloon control band has a proximal end located proximally of a proximal end of the balloon and a distal end located adjacent a proximal end of a received unexpanded stent. The distal balloon control band has a proximal end located adjacent a distal end of the received unexpanded stent and a distal end located distally of a distal end of the balloon. The balloon control bands each have a diametric cross-section larger than the balloon in an uninflated state and the unexpanded stent received over the balloon to impede axial movement of the unexpanded stent off of the balloon.

CROSS REFERENCE TO RELATED APPLICATIONS

This U.S. patent application is a continuation of, and claims priorityunder 35 U.S.C. §120 from, U.S. patent application Ser. No. 14/714,639,filed on May 18, 2015, which is a divisional of, and claims priorityunder 35 U.S.C. §121 from, U.S. patent application Ser. No. 12/969,189,filed on Dec. 15, 2010, which is a continuation-in-part of, and claimspriority under 35 U.S.C. §120 and 365(c) from, PCT Patent ApplicationPCT/US2010/028581, filed on Mar. 25, 2010, which claims priority under35 U.S.C. §119(e) to U.S. Provisional Application 61/163,103, filed onMar. 25, 2009. The disclosures of these prior applications areconsidered part of the disclosure of this application and are herebyincorporated by reference in their entireties.

TECHNICAL FIELD

This disclosure relates to medical apparatuses and specifically to aballoon catheter delivery apparatus and method for using andmanufacturing the same.

BACKGROUND

Balloon deliver apparatuses, or angioplasty balloons, are useful fortreating maladies in patients that involve the patients' vasculature.For example, angioplasty balloon dilation is sometimes used for thetreatment of stenosis, wherein a small balloon is disposed at thelocation of the stenosis and inflated to expand the stenosis in a vessellumen and improve the vessel's patency. Angioplasty balloons are alsouseful for deploying stents in a patient's vasculature that maintain thevessel's locally expanded state or patency and prevent restenosis. It isnoted that coronary stenting is believed to reduce restenosis rates inpatients when compared with conventional balloon dilation. Amer. J.Cardio. 2002, 90, 1187-1192. Fischell, et al. in U.S. Pat. Nos.6,375,660, 6,936,065 and 7,011,673 (“the Fischell patents”) show elasticbands that are placed over the ends of a stent delivery inflatableballoon that would help prevent stent embolization.

In either balloon angioplasty or stenting procedures, angioplastyballoons are typically used to expand a stenosis in a patient'svasculature. In procedures including the deployment of a stent, theangioplasty balloon may also expand and deploy the stent within thepatient's vasculature. These procedures are traditionally preceded bythe placement of a guidewire through the stenosis, which is followed byangioplasty balloon dilation at the stenosis with a balloon angioplastycatheter that has been advanced over the guidewire. The balloonangioplasty catheter is then withdrawn from the patient and a stentdelivery system that includes the stent is advanced over the guidewire,and the stent is then deployed at the site of the dilated stenosis.

Conventional stenting procedures include the following steps:

-   -   1. Place coronary guidewire into wire introducer;    -   2. Load guidewire into guiding catheter;    -   3. Advance guidewire across lesion;    -   4. Remove wire introducer;    -   5. Load predilatation balloon angioplasty catheter onto        guidewire;    -   6. Advance balloon catheter into guiding catheter;    -   7. Cross lesion with predilatation balloon;    -   8. Dilate lesion with balloon;    -   9. Angiography;    -   10. Remove predilatation balloon catheter;    -   11. Load stent delivery system (SDS) onto guidewire;    -   12. Advance SDS into guiding catheter;    -   13. Cross lesion with SDS;    -   14. Deploy stent at high pressure;    -   15. Angiography; and    -   16. Remove delivery system.

Because of the complexity of the procedure, conventional stenting ofteninvolves lengthy procedural times, prolonged exposure to radiation,lengthy administration of contrast agents, and great expense. J. Amer.Col. Cardio. 1999, 34, 1910-1915. Furthermore, the balloon predilationfollowed by stent placement often leads to major vascular trauma in apatient.

SUMMARY

The disclosure provides an apparatus and methods that improve thetreatment of stenosis in a patient when compared with conventionalstenting treatments. The apparatus and the methods of using theapparatus reduce vascular trauma in a patient, reduce procedural time,reduce a patient's exposure to radiation, reduce the administration of acontrast agent, and reduce costs using direct stenting procedures.

One aspect of the disclosure provides a balloon angioplasty cathetercapable of delivering a balloon expandable stent where the balloon hasballoon control bands that extend beyond the ends of the balloon ineither or both the proximal and distal directions. It is typical forsuch an inflatable balloon to have five separate sections that aredescribed as follows: 1) a central cylindrical section onto which thestent is mounted; 2) a distal cylindrical shaft that fixedly joins theballoon to the distal end of the stent delivery catheter which istypically an inner tube, which inner tube is designed to be advancedover a guide wire; 3) a distal conical section connected at its distalend to the balloon's distal cylindrical shaft and connected at itsproximal end to the central cylindrical section of the balloon; 4) aproximal cylindrical shaft that fixedly joins the balloon to the distalend of an outer tube, which tube forms a lumen with a torroidalcross-section between that outer tube and the inner tube though whichfluid can be introduced or removed to inflate or deflate the balloon;and 5) a proximal conical section connected at its proximal end to theto the proximal cylindrical shaft of the balloon and connected at itsdistal end to the central cylindrical section of the balloon.

The balloon control bands may attach to the body of the angioplastycatheter beyond the ends of the shafts of the inflatable balloon. Insome implementations, the proximal balloon control band attaches to theouter tube of the stent delivery catheter at a location proximal to theproximal end of the proximal cylindrical shaft of the balloon and thedistal balloon control band attach to the inner tube of the stentdelivery catheter at a location distal to the distal end of the distalcylindrical shaft of the balloon. In some examples, the catheter definesa slight gap between the ends of the mounted stent and the edges of theadjacent balloon control bands. This slight gap may be needed for easein manufacturing of the stent delivery catheter because the ballooncontrol bands may be placed first before crimping the stent onto thecentral cylindrical section of the balloon between the two stentretention (balloon control) bands. Since the stent length may varyslightly, and the precision for longitudinal placement during crimpingis not perfect, the manufacturing process is simplified when thedistance between the inner edges of the balloon control bands isslightly longer than the longest stent that will be crimped onto thecentral cylindrical section of the balloon. The balloon angioplastycatheter may include a fixed wire such as is shown U.S. Pat. Nos.6,375,660, 6,936,065 and 7,011,673, the entire contents of which arehereby incorporated by reference, or the catheter may be a rapidexchange or over-the-wire catheter having a distal end that slides overa separate guide wire.

The disclosed apparatus and methods may concern direct stentingprocedures for treating stenosis. Direct stenting using the apparatusand/or methods may generally involve the following steps:

-   -   1. Placing a peel away introducer over distal end of stent        delivery system;    -   2. Loading a stent delivery system into a guiding catheter and        removing the peel away introducer;    -   3. Advancing the stent delivery system across lesion;    -   4. Dilating a balloon of the delivery system and deploying the        stent at high pressure;    -   5. Angiography; and    -   6. Removing the delivery system.

Thus, direct stenting using the apparatus and/or methods offers fewersteps than conventional stenting; and consequently, procedural times areoften reduced by 20-30%, the patient's radiation exposure (e.g.,Fluoroscopy Time) is reduced by 20-30%, and the procedural cost is oftenreduced by 22-35%. Some implementations may provide some patients with areduced incidence of restenosis and/or a reduced MACE rate. It is alsonoted that the omission of the predilation step in direct stenting isbelieved to reduce vessel wall damage and distal embolization comparedwith conventional stenting. See e.g., J. Amer. Coll. Cardio. 2008, 51,1060-1065.

One aspect of the disclosure provides a balloon delivery catheter thatincludes a catheter tubing having a balloon near the distal end of thecatheter tubing. The balloon includes a distal end, a proximal end, andan intermediate segment. The balloon is nested between a distal ballooncontrol band and a proximal balloon control band. A core wire extendsthroughout a portion of the catheter and includes a proximal portion anda distal portion in which the distal portion of the core wire includes acoiled section that extends beyond the distal end of the balloon. Insome implementations, the balloon delivery catheter further includes astent disposed around the balloon such that when the balloon is inflatedthe inflated balloon expands the stent so that a radius of the stent isincreased. In some examples, the catheter includes a distal ballooncontrol band having a portion (e.g., the proximal end of the distalcontrol band) that has a larger profile (e.g., a larger diametric crosssection) than that of the unexpanded stent, so that when the balloon andstent are advanced to a stenosis site, the distal balloon control bandpushes through the stenosis leaving a channel having a size sufficientfor the stent. Moreover, the larger profile distal balloon control bandmay prevent any of the stent edges from catching on previously deployedstents thereby improving stent crossing in a patient's vasculature. Inconventional catheter systems, the balloon material distal to the stentcan be compressed as it is advanced into the stenosis and the distaledge of the stent can catch or engage a narrowed vessel wall orocclusion as it passes through the stenosis. These problems areadvantageously avoided using the disclosed catheter, which includes astent and a distal balloon control band having a larger profile than thestent, because the stent does not have and does not develop any exposededges during its advancement into the stenosis. Consequently, the stentdoes not typically catch on the narrowed vessel walls or occlusioncausing the stenosis.

Another aspect of the disclosure provides a stent delivery catheterincluding a catheter tubing defining a lumen therethrough, a balloondisposed near a distal end of the catheter tubing and moving betweendeflated and inflated states, and proximal and distal balloon controlbands concentrically arranged around respective proximal and distal endportions of the balloon. The proximal balloon control band has aproximal end located proximally of a proximal end of the balloon and adistal end located adjacent a proximal end of a received unexpandedstent. The distal balloon control band has a proximal end locatedadjacent a distal end of the received unexpanded stent and a distal endlocated distally of a distal end of the balloon. The balloon controlbands each have a diametric cross-section larger than the balloon in anuninflated state and the unexpanded stent received over the balloon toimpede axial movement of the unexpanded stent off of the balloon.

In some implementations, each balloon control band comprises an elasticmaterial that expands during inflation of the balloon and contracts upondeflation of the balloon. The proximal and distal balloon control bandsmay be secured to the respective proximal and distal end portions of theballoon. Moreover, the proximal end portion of the balloon and theproximal balloon control band can both be attached to the cathetertubing. In some examples, the proximal balloon control band is attachedat least partially to the balloon and at least partially to the cathetertubing. In additional examples, the distal balloon control band isattached at least partially to the balloon and at least partially to thecore wire. Each balloon control band may have a non-uniformcross-sectional thickness along an axial direction of the ballooncontrol band. In some implementations, each balloon control band hasfirst and second end portions. The first end portion has a largerdiametric cross-section than the second end portion. Moreover, the firstend portion of each balloon control band is disposed adjacent to areceived stent on the balloon.

Another aspect of the disclosure provides a method of manufacturing amedical device. The method includes disposing a balloon near a distalend of a catheter tubing. The balloon is movable between deflated andinflated states. The method further includes disposing an unexpandedstent over the balloon in an uninflated state, arranging a proximalballoon control band concentrically around a proximal end portion of theballoon, and arranging a distal balloon control band concentricallyaround a distal end portion of the balloon. The proximal balloon controlband has a proximal end located proximally of a proximal end of theballoon and a distal end located adjacent a proximal end of theunexpanded stent. The distal balloon control band has a proximal endlocated adjacent a distal end of the unexpanded stent and a distal endlocated distally of a distal end of the balloon. The balloon controlbands each have a diametric cross-section larger than the balloon in anuninflated state and the unexpanded stent received over the balloon toimpede axial movement of the unexpanded stent off of the balloon.

In some implementations, each balloon control band comprises an elasticmaterial that expands during inflation of the balloon and contracts upondeflation of the balloon. The method may include at least partiallysecuring the proximal and distal balloon control bands to the respectiveproximal and distal end portions of the balloon. In some examples, themethod includes affixing the proximal end portion of the balloon and theproximal balloon control band both to the catheter tubing. In additionalexamples, the method includes shaping the balloon control bands to havea non-uniform cross-sectional thickness along an axial direction of theballoon control band. Each balloon control band has first and second endportions. The first end portion may have a larger diametriccross-section than the second end portion. The method may includearranging the first end portion of each balloon control band adjacent toa received stent on the balloon.

In yet another aspect, a method of treating vascular stenosis includesinserting into a vessel of a patient a portion of a stent deliverycatheter. The stent delivery catheter includes a catheter tubingdefining a lumen therethrough, a balloon disposed near a distal end ofthe catheter tubing and moving between deflated and inflated states, andproximal and distal balloon control bands concentrically arranged aroundrespective proximal and distal end portions of the balloon. The proximalballoon control band has a proximal end located proximally of a proximalend of the balloon and a distal end located adjacent a proximal end of areceived unexpanded stent. The distal balloon control band has aproximal end located adjacent a distal end of the received unexpandedstent and a distal end located distally of a distal end of the balloon.The balloon control bands each have a diametric cross-section largerthan the balloon in an uninflated state and the unexpanded stentreceived over the balloon to impede axial movement of the unexpandedstent off of the balloon. The method includes advancing the balloonacross the vascular stenosis, inflating the balloon to compress thevascular stenosis, deflating the balloon, and removing the stentdelivery catheter from the patient.

In yet another aspect, a balloon angioplasty catheter includes acatheter tubing defining a lumen therethrough, and an inflatable balloonhaving a central cylindrical portion, a distal portion having a distalconical portion and a distal cylindrical shaft, and a proximal portionhaving a proximal conical portion and a proximal cylindrical shaft. Theproximal shaft of the inflatable balloon is fixedly attached to a distalend of the catheter tubing. A balloon control band is mounted coaxiallyover the distal portion of the inflatable balloon. The balloon controlband extends in a distal direction beyond the distal shaft of theinflatable balloon and has a proximal end located near a proximal end ofthe distal conical section of the balloon when the balloon is in anuninflated state.

In some implementations, the balloon angioplasty catheter includes aballoon expandable stent having a proximal end and a distal end. Thestent is mounted coaxially onto the central cylindrical section of theinflatable balloon with the distal end of the stent adjacent theproximal end of the balloon control band. In some examples, a separationdistance between the distal end of the stent and the proximal end of theballoon control band is less than about 2 mm. The balloon angioplastycatheter may include a fixed guide wire extending in a distal directionbeyond the distal end of the distal balloon shaft. In some examples, theballoon control band has a diametric cross-section larger than theballoon in an uninflated state and an unexpanded stent received over theballoon to impede axial movement of the unexpanded stent off of theballoon. For example, a maximum outer diameter of the balloon controlband may be within 1.0 mil of an outside diameter of an unexpanded stentreceived by the balloon. Moreover, a maximum outer diameter of theballoon control band can be between 1.0 mil and 3.0 mils greater than anouter diameter of an unexpanded stent received by the balloon.

The details of one or more implementations of the disclosure are setforth in the accompanying drawings and the description below. Otheraspects, features, and advantages will be apparent from the descriptionand drawings, and from the claims.

DESCRIPTION OF DRAWINGS

FIG. 1 is a side view of a balloon catheter delivery apparatus, in whichthe distal shaft portion is shown in partial longitudinal-sectional viewfor illustrative purposes.

FIG. 2 is a longitudinal-sectional view of a distal shaft portion of theballoon catheter delivery apparatus of FIG. 1.

FIG. 3 is an enlarged view of a portion of the distal shaft portionindicated by line 3 of FIG. 2.

FIG. 4 is an enlarged view of a portion of the distal shaft portionindicated by line 4 of FIG. 2.

FIG. 5 is an enlarged view of a portion of the distal shaft portionindicated by line 5 of FIG. 2.

FIG. 6 is an enlarged view of a portion of the distal shaft portionindicated by line 6 of FIG. 2.

FIG. 7 is an enlarged view of a portion of the distal shaft portionindicated by line 7 of FIG. 2.

FIG. 8 is a longitudinal-sectional view of an exemplary handle portionof the balloon catheter delivery apparatus, wherein the handle portionincludes an optional stop cock.

FIG. 9 is an enlarged view of a portion of the handle portion indicatedby line 10 of FIG. 8.

FIG. 10 is a perspective view of an exemplary handle portion and aproximal shaft portion of the balloon catheter apparatus of FIG. 1.

FIG. 11 is a longitudinal-sectional view of a distal shaft portion ofthe balloon catheter apparatus in an undeployed state.

FIG. 12 is a cross-sectional illustration of the distal shaft taken atabout line 12 of FIG. 11 and viewed in a proximal direction inaccordance with an example embodiment of the invention.

FIG. 13 is a plot of distal output (in degrees) as a function ofproximal input (in degrees) for an exemplary balloon catheter deliveryapparatus.

FIG. 14 is a plot of back-out force as a function of track position inan S-curve track, demonstrating that the apparatus is highlymaneuverable in a patient's vasculature.

FIG. 15 is a longitudinal cross section of an exemplary distal end of aballoon angioplasty catheter for stent delivery of either a rapidexchange or over-the wire type.

FIG. 16 is a longitudinal cross section of an exemplary distal end of aballoon angioplasty catheter having a fixed guide wire.

Like reference symbols in the various drawings indicate like elements.

DETAILED DESCRIPTION

The present disclosure relates generally to a balloon catheter deliveryapparatus that is useful for treating stenosis in a patient.

I. Definitions

As used herein, the terms “catheter” or “catheter tubing” are usedinterchangeably and refer to a tube that sized and shaped to be insertedinto a body cavity, duct, or vessel. Some catheters are formed of adistal portion and a proximal portion wherein the proximal portion is ahypotube, and the distal portion is a distal flexible tube. Cathetersmay have diameters of from about 0.3 mm to about 2.4 mm and lengths offrom about 70 cm to about 170 cm.

As used herein, the terms “catheter hypotube” or “hypotube” are usedinterchangeably and refer to a small metallic tube that often forms theproximal portion of a catheter. Hypotubes are generally sized and shapedto be inserted into a body cavity, duct, or vessel. For example, mayhave outer diameters of from about 0.3 mm to about 2.4 mm, and lengthsof from about 50 cm to about 140 cm (e.g., from about 70 cm to about 120cm). Metallic hypotubes may be treated (e.g., coated, polished,sterilized, any combination thereof, or the like) to improve its utilityas a portion of a catheter.

As used herein, a “distal flexible tube” is a component of a catheterlocated distal to a proximal portion. In some examples, the distalflexible tube has a greater flexibility than the proximal portion of thecatheter. In some implementations, the distal flexible tube is formedfrom a polymer such as silicone rubber. In other implementations, thedistal flexible tube has a diameter of from about 0.3 mm to about 2.4mm, and a length of from about 0.5 cm to about 20 cm (e.g., from about 1cm to about 10 cm).

As used herein, the terms “core wire” and “guide wire” are usedinterchangeably and refer to a small wire that extends from a distal tipof a catheter hypotube. In many instances, the distal tip of the corewire has a curved or rounded surface to inhibit its tendency to pierceor dissect a blood vessel. The term guide wire is also used inconjunction with a rapid exchange or over-the wire balloon angioplastycatheter to mean a separate wire over which the catheter is delivered.

As used herein, the term “balloon” and “balloon member” are usedinterchangeably and refer to a flexible inflatable container capable ofincreasing its volume upon inflation with a fluid and decreasing itsvolume upon deflation.

As used herein, “stainless steel” refers to any steel alloy with aminimum of about 10.5% chromium content by mass. It is noted thatstainless steel may be coated or otherwise treated to enhance one ormore of its physical properties. For instance, stainless steel may becoated with a polymer such as PTFE to reduce its coefficient of frictionor improve is chemical resistance.

As used herein, “PTFE” and “polytetrafluoroethylene” are usedinterchangeably and refer to a synthetic fluoropolymer oftetrafluoroethylene. One such polymer is known by the DuPont brand nameTeflon.

As used herein, “silicone rubber” refers to any rubber-like materialcomposed of silicone, carbon, hydrogen, or oxygen. In several instances,silocone rubber comprises a Si—O—Si polymer backbone. Exemplary siliconerubbers include polymethylsiloxane, polyethylsiloxane,polypropylsiloxane, any combination thereof, or the like.

As used herein, “depth marker”, “optical marker”, and “marker” are usedinterchangeably and refer to optically visible marks that identify agiven length or desired location on the catheter hypotube or the corewire. Some optical markers are observable in X-Ray scans of the catheterhypotube or core wire on which they are located. Other markers areoptically observable by the human eye under visible light conditions.Optical markers may include painted markers or structural markers thatattach to the catheter hypotube or the core wire (e.g., bands, notches,blocks, or the like).

As used herein, “affix” and “affixed” refer to the attachment of oneobject to another. Affixing includes bonding, welding, crimping, orotherwise adhering or attaching one object to another object.

II. Apparatus

The disclosed apparatus and methods offer several advantages overtraditional balloon angioplasty and conventional stenting, for example,by providing a balloon delivery catheter that includes a catheter tubinghaving a balloon near the distal end of the catheter tubing. The balloonincludes a distal end, a proximal end, and an intermediate segment. Theballoon can be nested between a distal balloon control band and aproximal balloon control band. The catheter may include core wireextending throughout a portion of the catheter and including a proximalportion and a distal portion in which the distal portion of the corewire includes a coiled section that extends beyond the distal end of theballoon. The catheter may reduce vasculature trauma experienced by apatient when compared with conventional balloon angioplasty orconventional stenting, because the proximal and distal balloon controlbands restrict longitudinal overexpansion of the balloon duringinflation. This restriction in overexpansion of the balloon affected bythe balloon control bands may reduce the trauma to the patient'svasculature and reduce the incidence of restenosis.

Referring to FIGS. 13 and 14, the balloon delivery catheter may provideimproved control and flexibility, which provides improvedmaneuverability through a patient's vasculature. FIG. 13 demonstratesthat the disclosed apparatus can provide excellent rotationalresponsiveness to a user's input rotation, and FIG. 14 demonstrates thatthe disclosed apparatus has excellent flexibility and can be withdrawnfrom bends around a series of alternating curves without the need ofexcessive force.

In some implementations, the balloon delivery catheter optionallyincludes a stent disposed around a balloon such that when the balloon isinflated, the inflated balloon expands the stent so that a radius of thestent increases. In some examples, the distal balloon control bandincludes at least a portion that has a greater profile, i.e., diametriccross section DC_(A) (FIG. 12), than the unexpanded stent disposed aboutthe balloon. These implementations may reduce the likelihood that thestent snags on a vessel wall or other occlusion at the stenosis site,because the larger profile distal control band pushes through thestenosis before the stent and creates a channel of suitable size foraccepting the stent. Moreover, these implementations may reduce thelikelihood that the leading edge of the stent snags on a vessel wall, apreviously deployed stent, or other occlusion in the patient'svasculature, because the larger profile distal balloon control bandreduces or altogether eliminates any exposed leading edges on the stentthat could catch on previously deployed stents or vessel wall in apatient's vasculature. In addition, the constriction applied at the endsof the balloon by the balloon control bands retracts the balloon to aminimum diameter so that the apparatus does not snag the stent uponwithdrawal of the apparatus from the patient.

In some implementations, a balloon delivery catheter apparatus includesan all-in-one stent delivery system comprising a fixed guide wire and acatheter including an elongate flexible hypotube having distal andproximal shaft portions and an inflatable balloon to which a stent mayoptionally be affixed thereto. The balloon may be in fluid communicationwith the lumen of the flexible hypotube. In some examples, the proximalend of the core wire is affixed to the distal end of the proximal shaftportion of the catheter hypotube and the distal tip of the core wireextends beyond the balloon. The balloon has a proximal end attached tothe distal section of the hypotube and a distal end attached to the corewire at a location proximal to the distal tip of the wire. The apparatusmay include balloon control bands that assist in stent deployment and/orvessel expansion by constricting dilation of the balloon at its proximaland distal ends, thereby encouraging the balloon midsection beneath thestent (if a stent is affixed to the balloon) to inflate and deploy atthe middle before the ends expand. In embodiments comprising theoptional stent, the balloon control bands restrict the overexpansion ofthe balloon and the stent affixed thereto at their respective ends—anevent that often causes trauma to vessel walls. This restriction inoverexpansion of the balloon caused by balloon control bands may reducethe incidence of restenosis in the patient. In addition, theconstriction applied at the ends of the balloon by the balloon controlbands retracts the balloon to a minimum diameter so that the apparatusdoes not snag the stent upon removal from the patient. In variousexamples, the profile of the apparatus may be minimized not only by theballoon control bands, but also by the various connections within theapparatus, many of the components being directly bonded to one another,for example, but not limited to, laser welding.

FIG. 1 provides a part side view, part longitudinal-sectionalillustrative view of a balloon catheter delivery apparatus 10, which mayalso be referred to as a stent-on-a-wire (SOAW) delivery catheter. Insome examples, the delivery apparatus 10 may be sterilized by anethylene oxide gas, radiation treatment (e.g., treatment with e-beam orgamma radiation), sterilizing solution, any combination thereof, orother sterilizing medium or procedure compatible with the materials usedin the balloon catheter delivery apparatus.

Although the foregoing description discloses a balloon catheter deliveryapparatus 10 that may be used for placing a stent S at, for example, astenosis V_(S) of a vessel V in, for example, a patient, (e.g., ahuman), other uses are possible. Accordingly, in some implementations,the delivery apparatus 10 may be utilized to treat, for example,ischemic heart disease. Further, the delivery apparatus 10 may also findutility as an angioplasty catheter that does not include a stent S orthe stent S may be removably affixed to the balloon catheter deliveryapparatus 10.

The delivery apparatus 10 may be used for placing an angioplasty ballooncatheter through a stenosis V_(S). The structure of delivery apparatus10 may enhance, for example, the pushability of an angioplasty catheterthat is utilized for dilating a stenosis V_(S).

A distal shaft portion 16 of the delivery apparatus 10 is shown in aslightly expanded or inflated state in the examples shown in FIGS. 1-7.The examples shown in FIGS. 11 and 12 illustrate the distal shaftportion 16 of the delivery apparatus 10 prior to inflation.

As seen in FIG. 1, an axis A-A extends through the delivery apparatus 10from a proximal end 10 a to a distal end 10 b. The delivery apparatus 10may optionally include a handle 12 having a proximal end 12 a and adistal end 12 b. The delivery apparatus 10 may also include a catheterhypotube that comprises a proximal shaft section 14 having a proximalend 14 a and a distal end 14 b. The catheter hypotube also comprises aproximal distal shaft portion 16 having a proximal end 16 a and a distalend 16 b.

The handle 12, the proximal shaft portion 14, and/or all or part of thedistal shaft portion 16 may form a lumen or passage allowing forinflation of a balloon 28 of the delivery apparatus 10. The proximal end14 a of the proximal shaft portion 14 may be fixedly or removablyconnected to the distal end 12 b of the handle 12. In some examples, thedistal end 12 b of the handle 12 is approximately 145 centimeters fromthe distal end 10 b of the delivery apparatus 10. Moreover, the distalend 14 b of the proximal shaft portion 14 may be fixedly or removablyconnected proximate to the proximal end 16 a of the distal shaft portion16. In some examples, the distal end 14 b of the proximal shaft portion14 is disposed within the distal shaft portion 16 proximate to theproximal end 16 a of the distal shaft portion 16 (see e.g., FIG. 4).Alternatively, the proximal end 16 a of the distal shaft portion 16 maybe disposed within the distal end 14 b of the proximal shaft portion 14.Other ways of connecting the handle 12, the proximal shaft portion 14and the distal shaft portion 16 are possible as well.

In some implementations, the delivery apparatus 10 functions in a mannerthat permits the stent, S, to be removably attached to the distal shaftportion 16. Further, the distal shaft portion 16 may retain the stent Sand later deploy the stent S at, for example, a stenosis V_(S) of avessel V of a human body. Upon deployment of the stent S, the deliveryapparatus 10 may be said to no longer include or retain the stent S.

The handle 12 and the proximal shaft portion 14 may function in a mannerthat permits communication of a fluid F from a fluid source F_(S) to thedistal shaft portion 16. In some examples, the handle 12 functions in amanner that permits or denies movement of the fluid F into or out of thedistal shaft portion 16 by way of the proximal shaft portion 14. Thefluid F may be pressurized to between about 8 and about 16 atmospheres.

Referring to FIGS. 1 and 2, in some implementations, the distal shaftportion 16 includes an axial core wire 18, a capped distal tip member20, a coil member 22, a distal balloon control band 24, a distal bondingportion 26, a balloon 28, a distal marker band 30, a proximal markerband 32, a proximal balloon control band 36, a distal shaft mountingportion 38 and a proximal shaft mounting portion 40.

Referring now to FIGS. 3 and 4, the core wire 18 may include a radialouter surface 42, a first, axial distal end segment 44 and a distal endsurface 48 (see e.g., FIG. 3) and a second, axial proximal end segment46 and a distal end surface 52 (see e.g., FIG. 4). As shown in FIGS. 1and 2, in some examples, the distal end segment 44 of the core wire 18may extend beyond the distal end of the balloon control band 24.

The radial outer surface 42 may define the core wire 18 to include asubstantially circular cross-section having an outer diameter D1. Theradial outer surface 42 is not limited, however, to defining the corewire 18 to include a substantially circular cross section and the corewire 18 may include any desirable cross-sectional shape, such as, forexample, a square, rectangular, hexagonal cross-section or the like. Inaddition, the shape of the core wire 18 may not be uniform. For example,a portion of the core wire 18 within the capped distal tip member 58 maybe substantially circular, while a portion of the core wire 18 that lieswithin the coil member 22 may be rectangular. The core wire 18 may taperas it extends axially from the proximal end 10 a to the distal end 10 b.The core wire 18 may also be coined. The tapering and coining of thecore wire 18 may permit the core wire 18 to be flexible and/orshapeable.

As seen in FIGS. 2 and 3, the first axial, distal, end segment 44 of thecore wire 18 may define, in part, a distal end 10 b of the deliveryapparatus 10. The first, axial distal end segment 44 may terminate in arounded, substantially dome-shaped distal end surface 48. As seen inFIGS. 2 and 4, the second axial, proximal, end segment 46 of the corewire 18 may be located axially away from the distal end 10 b of thedelivery apparatus 10 at any desirable axial distance/length. The secondaxial proximal end segment 46 may terminate in a proximal end surface52. The proximal end surface 52 may be connected directly to an innerwall 184 of the proximal shaft portion 14 by any suitable method, suchas, but not limited to, laser welding.

Referring to FIG. 3, in some implementations, the capped distal tipmember 20 defines, in part, the distal end 10 b of the deliveryapparatus 10. For example, the capped distal tip member 20 may be formedfrom or an integral part of the core wire 18, or, alternatively, thecapped distal tip member 20 may be formed as a separate component, asillustrated, from that of the core wire 18.

The capped distal tip member 20 may define a cup-shaped body 58 having asubstantially U-shaped longitudinal section. The cup-shaped body 58 mayinclude a distal, dome-shaped outer axial surface 60 and a proximal,recessed axial surface 62 that corresponds to and may be axiallydisposed adjacent the rounded, substantially dome-shaped axial/distalend surface 48 of the core wire 18. In some examples, the recessed axialsurface 62 is heat-bonded with the axial/distal end surface 48 of thecore wire 18. In additional examples, the distal portion of the corewire 18 is melted, with a laser welder or by other suitable means, toform the integral capped distal tip member 20.

The proximal, recessed axial surface 62 of the capped distal tip member20 may extend axially toward the proximal end 10 a of the deliveryapparatus 10 to define a substantially annular (in cross-section) axialproximal end surface 64 around the radial outer surface 42 of the corewire 18. The substantially annular axial proximal end surface 64 mayextend to an outer radial side surface 66 that extends to the distal,dome-shaped outer axial surface 60. The connection of the substantiallyannular, axial end surface 64 and the outer radial side surface 66 maydefine a diameter D2 of the capped distal tip member 20. In someexamples, the diameter D2 may be greater than the diameter D1 of corewire 18.

The coil member 22 may be composed of, but is not limited to, aplatinum-iridium (Pt/Ir) material in whole or in part. As shown in FIG.3, the coil member 22 may generally define an inner surface 23 and anouter surface 25. In some examples, the inner surface 23 defines apassage 27 with a diameter that is approximately the same as, butslightly greater than the diameter D1 of core wire 18, to permit thecore wire 18 to extend through the passage 27 so that the coil member 22may be arranged concentrically relative to the core wire 18. Moreover,the coil member 22 may be radiopaque.

The outer surface 25 of the coil member 22 may define the coil member 22to have an outer diameter substantially equal to or less than thediameter D2 of the capped distal tip member 20. The outer diameter D2 ofthe coil member 22 may be approximately, but is not limited to, 0.012inches. In some examples, the coil member 22 has any desirable axiallength, for instance, but not limited to, approximately 22 millimeters.As shown in FIG. 5, in some implementations, the proximal portion of thecoil member 22 may be stretched to create a series of spaces 22 abetween individual coils.

Referring back to FIGS. 2 and 3, the coil member 22 may be disposedsubstantially adjacent to either of or both of the radial outer surface42 of the core wire 18 and the substantially circular, axial end surface64 of the capped distal tip member 20. The coil member 22 may be fixedlyconnected or joined to one or more of the radial outer surface 42 andthe substantially annular, axial end surface 64. The coil member 22 maybe connected or joined to either or both surfaces 42, 64 via anysuitable methodology such as, for example, a laser-welding operation. Insome examples, the outer surface 25 of the coil member 22 is heat-bondedwith an inner surface 130 of the distal balloon control band 24, shownin FIG. 5. The inner surface 130 of the distal balloon control band 24may extend into the spaces 22 a (not shown).

The cup-shaped body 58 of the capped distal tip member 20 may help tofunctionally prevent the coil member 22 from axially moving and/orradially separating (i.e., uncoiling) along the core wire 18. Further,the geometry of the rounded, dome-shape surface 60 of the capped distaltip 20 may functionally provide the delivery apparatus 10 with aradiused, atraumatic tip.

Referring to FIG. 5, the distal bonding portion 26 may include, but isnot limited to, a substantially cylindrical body, sleeve or tube 68having an inner radial surface 70 and an outer radial surface 72. Theouter radial surface 72 may define a diameter D3. The inner radialsurface 70 may define a diameter that may be approximately the same as,but slightly greater than diameter D2 (see e.g., FIG. 3).

The distal bonding portion 26 may include a low-density polyethylene(LDPE) material or the like. In some examples, the distal bondingportion 26 is utilized to bond the coil member 22 with one or more ofthe balloon 28 and the distal balloon control band 24, which may preventtwisting of the balloon 28 on the core wire 18. Bonding between othercomponents, such as the coil member 22 and the distal balloon controlband 24 and the distal bonding portion 26 or other reshaping of thebonding portion 26 may be activated by, for example, treatment of thebonding portion 26 with a laser. The distal bonding portion 26 mayextend into the spaces 22 a. In some examples, the coil member 22 isstretched to permit the distal bonding portion 26 to extend into thespaces 22 a.

The substantially cylindrical tube 68 may be concentrically arrangedrelative to the core wire 18 and the coil member 22 such that one ormore of the core wire 18 and the coil member 22 extends through apassage 74 defined by the inner radial surface 70 of the substantiallycylindrical tube 68 of the distal bonding portion 26. The inner radialsurface 70 may be disposed adjacent to the outer radial surface 25 ofthe coil member 22.

Referring to FIG. 6, one or more of the distal shaft mounting portion 38and the proximal shaft mounting portion 40 may include, but are notlimited to, a polymeric material such as a polyamide material. Aproximal end of the distal shaft mounting portion 38 may be heat-bondedto a distal end of the proximal shaft mounting portion 40. Although thedistal and proximal shaft mounting portions 38, 40 may include apolymeric material in some embodiments, the durometer (i.e., thehardness/softness) of the polymeric material may not necessarily be thesame between or within the shaft mounting portions 38, 40. For instance,the hardness/softness of the proximal shaft portion 14, proximal shaftmounting portion 40, and the distal shaft mounting portion 38 can eachbe selected such that the proximal shaft portion 14 is more rigid thanthe proximal shaft mounting portion 40 and the distal shaft mountingportion 38, and the proximal shaft mounting portion 40 is more flexiblethan the proximal shaft portion 14, but less flexible than the distalshaft mounting portion 38. In this configuration, the proximal shaftportion 14 provides rigidity to the apparatus and the proximal shaftmounting portion 40 and the distal shaft mounting portion 38 providesufficient flexibility to navigate coronary or other vessel anatomy asthe distal shaft portion 16 is positioned for deployment.

Figures illustrating the proximal shaft portion 14, the proximal shaftmounting portion 40, the distal shaft mounting portion 38 and the distalshaft portion 16 are not drawn to scale and are merely a convenientrepresentation of those components. The relative lengths of thesecomponents can vary as necessary to provide an apparatus that can beused to navigate coronary or other vessel anatomy. For instance, therelative lengths of proximal shaft mounting portion 40 and the distalshaft mounting portion 38 can be approximately 15 centimeters and 35centimeters, respectively.

As illustrated in FIG. 6, the distal shaft mounting portion 38 mayinclude, but is not limited to, a substantially cylindrical body, sleeveor tube 76 having an inner radial surface 78 and an outer radial surface80, an axial distal end surface 82 and an axial proximal end surface 84.A passage 90 that may be defined by the inner radial surface 78 may havean inner diameter D6 that extends axially through the distal shaftmounting portion 38 from the axial proximal end surface 84 to the axialdistal end surface 82. The distal shaft mounting portion 38 may beconcentrically arranged relative to the core wire 18 such that the corewire 18 axially extends through the passage 90.

In some embodiments, a proximal portion of the proximal balloon controlband 36 is bonded to the outer radial surface 80 of a distal end of thedistal shaft mounting portion 38, by any suitable method, such as bylaser welding. The area of the outer radial surface covered by theproximal portion of the proximal balloon control band 36, i.e., area 86,may extend part or all of the way over the outer radial surface 80 ofdistal shaft mounting portion 38. The distal portion of proximal ballooncontrol band 36 may extend radially around the proximal portion ofballoon 28. The distal portion of the proximal balloon control band 36may be made of a material that will stretch as axial chamber 174 asdefined by balloon 28 is inflated and snap back or relax into itsinitial position when axial chamber 174 as defined by balloon 28 isdeflated, thereby helping to collapse the balloon 28 and minimize theprofile of the apparatus following balloon 28 deflation. In someexamples, a proximal bonding portion may secure the proximal ballooncontrol band 36 to the distal end of the distal shaft mounting portion38 (not shown).

Referring to FIGS. 2 and 5-7, the balloon 28 may include, but is notlimited to, for example, a nylon material. The balloon 28 may include adistal segment 106 (see e.g., FIG. 5), an intermediate segment 108 (seee.g., FIG. 7) and a proximal segment 110 (see e.g., FIG. 6) collectivelydefining an inner surface 112 and an outer surface 114 of the balloon28.

Referring to FIG. 5, in some implementations, a portion 116 of the innersurface 112 of the distal segment 106 of the balloon 28 may be arrangedadjacent to a portion 118 of the outer radial surface 72 of the distalbonding portion 26. Similarly, referring to FIG. 6, in someimplementations, a portion 120 of the inner surface 112 of the proximalsegment 110 of the balloon 28 may be arranged adjacent to the outerradial surface 80 of the distal shaft mounting portion 38. The innersurface 112 of the portion 120 of the balloon 28 may be bonded to thedistal end of distal shaft mounting portion 38, by, for instance, butnot limited to laser welding, thereby minimizing the profile ofapparatus 10.

With further reference to FIG. 5, the distal balloon control band 24 mayinclude a distal segment 124, an intermediate segment 126 and a proximalsegment 128 that collectively define an inner surface 130 and an outersurface 132 of the distal balloon control band 24. In some examples, theouter surface 132 of distal balloon control band 24 generally definesthe distal balloon control band 24 to form a conical outer surfacetapering in the distal direction.

The distal segment 124 of the distal balloon control band 24 may bearranged concentrically with respect to the core wire 18 and the coilmember 22. The inner surface 130 may define the distal balloon controlband 24 to include a passage 134 that permits one or more of the corewire 18, the coil member 22, the distal bonding portion 26, and theballoon 28 to axially extend through the distal control band 24.

The passage 134 may include a constant or a non-constant diameter (e.g.,creating a tapering, widening, constricting, and/or expanding passage134) for one or more of the segments 124, 126, and 128. For instance,the passage 134 may decrease in diameter, as shown in FIG. 5, as thedistal balloon control band 24 extends from the proximal end 10 a towardthe distal end 10 b of the delivery apparatus 10.

In some examples, one or more of the core wire 18, the coil member 22and the distal bonding portion 26 axially extend through the passage 134proximate to one or more of the distal segment 124 and the intermediatesegment 126 of the distal balloon control band 24. The inner surface 130of the distal segment 124 of the distal balloon control band 24 may bedisposed substantially adjacent and attached to one or more of the outersurface 25 of the coil member 22 and a portion 136 of the outer surface72 of the distal bonding portion 26.

The intermediate segment 126 of the distal balloon control band 24 maybe arranged concentrically with respect to one or more of the core wire18, the coil member 22, the distal bonding portion 26 and a portion ofthe distal segment 106 of the balloon 28. The inner surface 130 of theintermediate segment 126 of the distal balloon control band 24 may bedisposed adjacent to a portion 138 of the outer surface 114 of thedistal segment 106 of the balloon 28. The portion 138 can be referred toas a distal step portion or a distal tubular portion of the balloon 28.

The proximal segment 128 of the distal balloon control band 24 may bearranged concentrically with respect to one or more of the core wire 18,a portion of the axial length of the coil member 22, and a portion ofthe distal segment 106 of the balloon 28. The inner surface 130 of theproximal segment 128 of the distal balloon control band 24 may bedisposed adjacent to a portion 140 of the outer surface 114 of thedistal segment 106 of the balloon 28. The portion 140 may be referred toas a distal ramp portion or distal conical portion of the balloon 28.The distal conical portion 140 may be connected to the distal tubularportion 138 of the balloon 28.

Referring to FIG. 6, the proximal balloon control band 36 may include adistal segment 144, an intermediate segment 146 and a proximal segment148 collectively defining an inner surface 150 and an outer surface 152.The outer surface 152 of the proximal balloon control band 36 may definethe proximal balloon control band to include a proximal outer conicalportion, tapering in the proximal direction.

The distal segment 144 of the proximal balloon control band 36 may bearranged concentrically with respect to one or more of the core wire 18and a portion 154 of the balloon 28. A portion 156 of the inner surface150 of the proximal balloon control band 36 may be disposedsubstantially adjacent and attached to a portion 158 of the outersurface 114 of the proximal segment 110 of balloon 28. The portion 158can be referred to as a proximal ramp portion or the proximal conicalportion of the balloon 28.

Intermediate segment 146 of the proximal balloon control band 36 may bearranged concentrically with respect to one or more of the core wire 18,the distal shaft mounting portion 38 and the proximal segment 110 of theballoon 28. A portion 160 of the inner surface 150 of the proximalballoon control band 36 may be disposed adjacent a portion 162 of theouter surface 114 of the proximal segment 110 of the balloon 28. Theportion 162 can be referred to as a proximal tubular portion of theballoon 28. The proximal conical portion 158 of the balloon 28 may beconnected to the proximal tubular portion 162 of the balloon 28.

The proximal segment 148 of the proximal balloon control band 36 may bearranged concentrically with respect to one or more of the core wire 18,a portion 120 of the balloon 28, and a portion 170 of the distal shaftmounting portion 38. A portion 164 of the inner surface 150 of theproximal segment 148 of the proximal balloon control band 36 may bedisposed substantially adjacent to the portion 170 of the outer radialsurface 80 of the distal shaft mounting portion 38.

The proximal balloon control band 36 may define an axial passage 171that permits one or more of the core wire 18, the proximal segment 110of the balloon 28, and the distal shaft mounting portion 38 to axiallyextend therethrough. Further, the passage 171 may include a constant ornon-constant diameter for one or more segments 144, 146, 148 of theproximal balloon control band 36 and/or may increase in diameter as theproximal balloon control band 36 extends from the proximal end 10 atoward the distal end 10 b of the delivery apparatus 10.

The proximal control bands 36 and distal balloon control bands 24 mayapply pressure to the proximal segments 110 and the distal segment 106of the balloon 28. When fluid F moves into the balloon 28, causingdilation of the balloon 28, the pressure applied by the proximal anddistal balloon control bands 36, 24 at the proximal and distal segments110, 106 of the balloon 28 encourages inflation at the intermediatesegment 108 of the balloon 28 first relative to the ends. This improvesuniform stent deployment by promoting uncrimping of the stent S at itsmiddle rather than at the distal and proximal ends of the stent S,thereby minimizing over expansion at the ends of the stent S and/orpreventing vessel tissue trauma distal and/or proximal to the deployedstent S and area of stenosis. In addition, the pressure applied by theproximal and distal balloon control bands 36, 24 to the proximal anddistal segments 110, 106 of the balloon 28 may assist with balloondeflation after stent deployment. As the fluid F is removed from theapparatus 10, the pressure applied by the balloon control bands 36, 24assists in collapsing the proximal and distal balloon segments 110, 106.This minimizes the profile of the balloon 28 so that it can be removedfrom the vessel V without snagging the vessel wall or the deployed stentS.

FIG. 7 depicts an exemplary intermediate segment 108 of the balloon 28and a portion of the stent S. In some implementations, the stent Sdefines an inner radial surface S_(RI) and an outer radial surfaceS_(RO). The inner radial surface S_(RI) of stent S may bedisposed/stowed substantially adjacent to the outer surface 114 of theballoon 28 before/during the axial carrying/delivery of the stent Swithin the vessel V. In some examples, the inner radial surface S_(RI)of the stent S is crimped onto the outer surface 114 of the balloon 28.

The intermediate segment 108 of the balloon 28 may also be referred toas an intermediate tubular portion of the balloon 28. The outer surface114 of the intermediate tubular portion 108, taken together with theouter surface S_(RO) of stent S may have a generally constant diameterD7. The intermediate tubular portion 108 may be arranged between andconnect the distal and proximal conical portions of the balloon 28.

The balloon 28 may be expanded from a retracted orientation as shown inthe figures to an expanded/inflated orientation (not shown). Theexpansion/inflation of the balloon 28 may be caused by the receivedfluid F (see e.g., FIG. 1), which may be moved into an axial chamber 174of the balloon 28 as defined by its inner surface 112. In some examples,the fluid F is prevented from leaking into the vessel V by a sealbetween the distal and proximal balloon member segments 106, 110 and thedistal and proximal balloon control bands 24, 36 and/or the distalbonding portion 26 and the shaft mounting portion 38. Movement of thefluid F into the axial chamber 174 may be permitted by the handle 12 andthe proximal shaft portion 14.

When the balloon 28 is expanded/inflated, the outer surface 114 of theballoon 28 imparts a radially, outwardly directed force to the innerradial surface S_(RI) of the stent S, such that the outer diameter D7 ofthe stent S is increased to a diameter that is greater than the diameterD7 at insertion of the apparatus 10 and the stent S is said to be movedto a deployed orientation. Deployment of the stent S may ultimatelyresult in the outer radial surface S_(RO) of the stent S imparting aradially outwardly directed force to the stenosis V_(S) of the vessel V.

Upon placing the stent S adjacent to and against the stenosis V_(S) ofthe vessel V, the fluid F may be removed from the axial chamber 174 ofthe balloon 28 such that the outer surface 114 of the balloon 28 isretracted radially away from the stent S and stenosis V_(S) of thevessel V. When the balloon 28 is moved from the expanded/inflatedorientation back to the retracted/non-inflated orientation, the innerradial surface S_(RI) of the stent S may remain in place adjacent to andagainst the stenosis V_(S) of the vessel V and be no longer in contactwith any portion of the delivery apparatus 10. The distal ballooncontrol band 24 and the proximal balloon control band 36 may include anelastic and/or rigid materials that assist in the forcing of the fluid Fout of the balloon 28, such that the balloon 28 may becollapsed/retracted to its non-inflated orientation.

Referring now to FIGS. 2 and 6, the second axial/proximal end 84 of thedistal shaft mounting portion 38 may be disposed adjacent to andconnected/joined to a first axial/distal end 176 of the proximal shaftmounting portion 40. As shown in FIG. 6, the core wire 18 may extendtoward the proximal end 10 a of the delivery apparatus 10, through thepassage 90 of the distal shaft mounting portion 38 and into a passage178 that may be defined a first inner radial surface 180 of the proximalshaft mounting portion 40. The passage 178 may define an inner diameterthat is approximately equal to the diameter D6.

Referring to FIG. 2 and the expanded view in FIG. 4, the core wire 18may extend further toward the proximal end 10 a of the deliveryapparatus 10 and through the passage 178 such that the second, axialproximal end segment 46 of the core wire 18 may be disposed within orproximate to a passage 182 of the distal end 14 b of the proximal shaftportion 14. The length of passage 182 containing the core wire 18, i.e.,the passage 202, may be any suitable distance, allowing for improvedattachment and reduced kinking (where proximal shaft portion 14comprises a catheter) of the proximal shaft portion 14 near the site ofattachment to the distal shaft portion 16. In some embodiments, thepassage 182 may be defined by an inner surface 184 of the proximal shaftportion 14.

One or more of the second axial end segment 46 of the core wire 18 andan axial/proximal end surface 186 of the proximal shaft mounting portion40 permits the distal shaft portion 16 to be connected to the proximalshaft portion 14. In some examples, one or more of the axial/proximalend surface 186 of the proximal shaft mounting portion 40 may bedisposed adjacent and connected/joined to a first axial/distal endsurface 188 of the proximal shaft portion 14.

A second inner radial surface 190 of the proximal shaft mounting portion40 may define an inner diameter, D8. In some examples, an outer radialsurface 192 of the proximal shaft portion 14 may include a diameter thatis approximately the same as but less than the diameter D8. The secondinner radial surface 190 of the proximal shaft mounting portion 40 maybe disposed adjacent to and connected/joined to the outer radial surface192 of the proximal shaft portion 14.

Referring to FIG. 4, a portion of the core wire 18 near the proximal end52 can be connected to the inner surface 184 of the proximal shaftportion 14, by any suitable method, such as, for example, laser welding.

FIG. 8 depicts an exemplary arrangement of the handle 12, the proximalshaft portion 14 and the proximal end 16 a of the distal shaft portion16. In some implementations, the proximal shaft portion 14 isultra-violet (UV) adhesive-bonded to the handle 12.

As seen in FIGS. 8-10, the handle 12 may include a docking torqueapparatus 206, which may include a base portion 208, a collet portion210, and a head portion 212. The base portion 208 and the head portion212 may include an acrylonitrile butadiene styrene (ABS) material. Thecollet portion 210 may include a brass material. In some examples, wherethe handle comprises two pieces, the collet portion 210 and thecylindrical socket portion 224 are integral, i.e., combined to form aunitary piece.

Referring to FIG. 9, the base portion 208 may include a firstaxial/distal end 214, a second axial/distal end 216, a firstaxial/proximal end 218 and a second axial/proximal end 220. The baseportion 208 may include a substantially cylindrical sleeve portion 222and a substantially cylindrical socket portion 224. The substantiallycylindrical sleeve portion 222 may be integrally formed with thesubstantially cylindrical socket portion 224.

The substantially cylindrical sleeve portion 222 may extend axially fromthe first axial/proximal end 218 to the second axial/distal end 216. Thesubstantially cylindrical socket portion 224 may extend axially from thesecond axial/distal end 216 to the first axial/distal end 214.

The base portion 208 may include an inner radial surface 226 that maydefine an axial passage 228 with an internal diameter D9. The colletportion 210 may include a substantially tubular sleeve portion 230connected to a chuck portion 232. The substantially tubular sleeveportion 230 may define the collet portion 210 to include a firstproximal end surface 234 connected to a first outer radial surface 236that is connected to a second proximal end surface 238 of the chuckportion 232. The second proximal end surface 238 of the chuck portion232 may be connected to a second outer radial surface 240 of the chuckportion 232 that is connected to a distal end surface 242 of the chuckportion 232. The substantially tubular sleeve portion 230 and the chuckportion 232 may define an inner radial surface 244 that defines an axialpassage 246 that extends axially from the first proximal end surface 234to the distal end surface 242.

The first outer radial surface 236 of the collet portion 210 may includea diameter approximately equal to but less than the diameter D9 of theaxial passage 228 of the base portion 208. The axial passage 246 of thecollet portion 210 may include an inner diameter that may beapproximately equal to but slightly greater than the outer diameter D8of the proximal shaft portion 14.

The head portion 212 may include a U-shaped cross-section having a firstinner radial surface 248, a second inner radial surface 250, anaxial/proximal surface 252 and an axial/distal surface 254. The firstinner radial surface 248 may include a diameter D10 that may beapproximately similar to, but slightly greater than, an outer diameterof the substantially cylindrical socket portion 224 of the base portion208. The second inner radial surface 250 may define the head portion 212to include a passage 256 that is approximately the same as, but slightlygreater than, the outer diameter D8 of the proximal shaft portion 14.

The substantially tubular sleeve portion 230 of the collet portion 210may be axially disposed within the axial passage 228 of thesubstantially cylindrical socket portion 224 such that the secondproximal end surface 238 of the chuck portion 232 may be arrangedsubstantially adjacent/proximate/opposingly facing a chamfered/conicalsurface 258 of the first axial/distal end 214 of the substantiallycylindrical socket portion 224.

The first inner radial surface 248 of the head portion 212 may include athreaded surface 260 that connectably interfaces with acorrespondingly-threaded surface 262 formed on an outer radial surface264 of the substantially cylindrical socket portion 224. The threadedconnected of the head portion 212 and the substantially cylindricalsocket portion 224 of the base portion 208 permits the head portion 212to be axially movable according to the direction of arrows, X (i.e.,axially toward the distal end 10 b), X′ (axially toward the proximal end10 a), relative one or more of the base portion 208, collet portion 210and the proximal end 14 a of the proximal shaft portion 14.

As seen in FIG. 9, the proximal shaft portion 14 may be axially insertedthrough the passage 256 of the head portion 212 and into the axialpassage 246 of the collet portion 210. As such, upon axially moving thehead portion 212 according to the direction of the arrow, X′, anaxial/proximal surface 266 of the head portion 212 may come into contactwith the distal end surface 242 of the chuck portion 232 such that thesecond proximal end surface 238 of the chuck portion 232 may come intocontact with the chamfered/conical surface 258 of the first axial/distalend 214 of the substantially cylindrical socket portion 224.

As the second proximal end surface 238 comes into contact with thechamfered/conical surface 258, the axial passage 246 of the colletportion 210 at least proximate to the chuck portion 232 may be radiallyreduced such that the inner radial surface 244, at least proximate tothe chuck portion 232, may engage, grip, /or “bite into” a portion 267of the outer radial surface 192 proximate to at least the proximal end14 a of the proximal shaft portion 14. The engagement of the chuckportion 232 and the proximal end 14 a of the proximal shaft portion 14may provide a frictional, axially-selective connection of the handle 12and the proximal shaft portion 14.

Referring to FIGS. 8-10, the handle 12 may also include a handle body268, an optional stopcock 270, and a strain relief member 272. Thehandle body 268 may axially extend from the proximal end 10 a toward thedistal end 10 b of the delivery apparatus 10 to define a nose portion274 that is press-fitted to the strain relief member 272. The strainrelief member 272 may be axially connected to one or more of the firstaxial/proximal end 218 and the second axial/proximal end 220 of the baseportion 208.

The optional stopcock 270 may be inserted through a radial passage 276formed in the handle body 268. In some examples, the optional stopcock270 may be press-fitted to the handle body 268 such that the stopcock270 may be rotatably connected to the handle body 268 (e.g., to permitthe stopcock 270 to be able to turn 90° in a “quarter-turn” orientationrelative to the handle body 268 and within the radial passage 276). Theoptionally integrated stopcock may effectuate a time savings because theuser will not have to assemble the stopcock as an additional part withthe delivery apparatus 10.

The stopcock 270 may include an axially-alignable passage 278. Rotationof the stopcock 270 permits the stopcock to act as a valve member topermit or deny movement of the fluid, F, through the handle body 268.

The stopcock 270 may be rotatably-connected to the handle body 268 suchthat the axial passage 278 of the stopcock 270 may be axially alignedwith an axial passage 280 extending through the handle body 268 and anaxial passage 282 extending through the strain relief member 272.Accordingly, as seen in FIG. 8, the axial passage 278 may be axiallyaligned with the axial passages 280, 282 of the handle body 268 and thestrain relief member 272. The fluid F may be provided through the axialpassages 228, 246, 256, 278, 280, 282 of the handle 12, through theaxial passages 182, 202 of the proximal shaft portion 14 and through theaxial passages 90, 178 (see, e.g., FIGS. 4 and 6) of the distal shaftportion 12 and into the axial chamber 174 of the balloon 28. Thepassages 90, 178, 182, 202, 228, 246, 256, 278, 280 and 282 may be influid communication with one another and axial chamber 174 in order topermit the fluid F to be moved into the balloon 28 in order to permitthe balloon 28 to be moved to an inflated orientation and deploy thestent S.

In some implementations, the handle body 268 does not include thestopcock 270. A valve may be located upstream of the handle body 268 tocontrol flow into the axial passage 280 of the handle body 268.

Referring to FIGS. 1 and 10, the proximal shaft portion 14 may include astainless steel material and the outer radial surface 192 of theproximal shaft portion may be coated with a polytetrafluoroethylene(PTFE) material. The outer radial surface 192 may include a proximaldepth marker 284 and a distal depth marker 286 formed on outer radialsurface 192 of the proximal shaft portion 14. The proximal depth marker284 may be arranged on the outer radial surface 192 approximately 100centimeters from the distal end 10 b of the delivery apparatus 10. Thedistal depth marker 286 may be arranged on the outer radial surface 192approximately 90 centimeters from the distal end 10 b of the deliveryapparatus 10.

Referring to FIGS. 2, 5 and 7, the proximal marker band 32 and thedistal marker band 34 may be formed on the radial outer surface 42 ofthe core wire 18. The proximal marker band 32 permits a user to gaugethe approximate axial location of where the proximal segment 110 andintermediate segment 108 of the balloon 28 are joined together. Thedistal marker band 34 permits the user to know of an approximate axiallocation of where the distal segment 106 and intermediate segment 108 ofthe balloon 28 are joined together. As such, by knowing the location ofthe segments 106-110 of the balloon 28, the user may also know theapproximate axial location of the stent S as well.

Each of the proximal and distal marker bands 32, 34 may include an innerradial surface 288 and an outer radial surface 290. The inner radialsurface 288 may be connectively swaged to the radial outer surface 42 ofthe core wire 18. The proximal and distal marker bands 32, 34 mayinclude any desirable material, such as, for example, a platinum-iridiummaterial.

Referring to FIGS. 1 and 2, one or more protective tubular members 292may be arranged coaxially relative to the core wire 18 and the proximaland distal marker bands 32, 34.

The protective tubular member 292 may include an inner radial surface294 and an outer radial surface 296. The outer radial surface 296 maydefine an outer diameter D11. The inner radial surface 294 may bearranged adjacent to the outer radial surface 290 of the proximal anddistal marker bands 30, 32. The protective tubular member 292 mayinclude any desirable material, such as a polymer. An example of apolymer material includes, without limitation, a polyamide material.

The protective tubular member 292 may prevent the inner surface 112 ofthe balloon 28 from contacting the outer radial surface 290 of theproximal and distal marker bands 32, 34. By preventing the inner surface112 of the balloon 28 from contacting the outer radial surface 290 ofthe proximal and distal marker bands 32, 34, any axial shifting of theproximal and distal marker bands 32, 34 relative the core wire 18 may bereduced/eliminated as the delivery apparatus 10 is being inserted intothe vessel, V. In addition, the protective tubular member 292 mayprevent the stent from being compressed to a diameter so small that itcannot be properly deployed.

In some implementations, the distal shaft portion 16 of the deliveryapparatus 10 may be coated with a friction-reducing material that mayassist a user in the inserting or removing the delivery apparatus 10.The coating may include a hydrophillic coating, which may include apolymer-based material. Not every element 18-40 of the distal shaftportion 16 may be coated with the friction-reducing material. Forexample, the balloon 28 may not be coated with the friction-reducingmaterial. Further, although the stent S may not necessarily beconsidered to be part of the delivery apparatus 10, the stent S may alsonot be coated with the friction-reducing material.

A protective polytetrafluoroethylene (PTFE) tubular sheath (not shown)may be arranged about the outer radial surface S_(RO) of the stent S orthe catheter tubing. The sheath may be provided with the deliveryapparatus 10 if, for example, the stent S is arranged relative to thedelivery apparatus in a “pre-mounted” configuration. Accordingly, priorto utilizing the delivery apparatus 10, a user may remove the sheath inorder to expose the stent S.

In some implementations, the axial core wire 18 may include a stainlesssteel material. Moreover, the distal balloon control band 24 may includea polyurethane material and the handle body 268 may include apolycarbonate (PC) material. The stopcock 270 may include an acetalmaterial. The strain relief member 272 may include a thermoplasticpolyether material, a polybutylene material, a terphthalate material, apolyether glycol material or the like.

One or more of the structures of the shaft portions 18-40, may include amaterial that lends itself to having a non-rigid, shapeable quality.Further, one or more of the structures 18-40 may include a material thatlends itself to having similar or dissimilar durometers (i.e.,softness/hardness ratings). Further, although the distal shaft portion16 is described to include structures identified at 18-40, the distalshaft portion 16 is not limited to the number of, type or geometry ofstructure identified at 18-40 and that the invention may be practicedwith any desirable number of, type or geometry of structure.

The balloon 28 may be folded upon itself one or more times. Accordingly,although the balloon 28 is illustrated in FIGS. 1, 2, 5, 6, and 7 toinclude one, non-folded layer, the illustration of the balloon 28 in thefigures does not limit the disclosed structure or function of theinvention. Various balloon folding, combinable with this disclosure, canbe found in U.S. Pat. No. 6,071,285 and U.S. Pat. No. 6,120,533, whichare hereby incorporated by reference in their entireties.

Referring to FIGS. 11 and 12, the distal shaft portion 16 is shown priorto inflation. FIGS. 11 and 12 also illustrate a “folded balloon” inwhich the balloon is folded upon itself. Although, for simplicity, theballoon is shown as being folded on itself three times, the balloon canbe folded in any manner. FIG. 11 (and also FIG. 2) clearly shows theplacement of the balloon control bands 24 and 36 over the inflatableballoon 28 during manufacturing. Specifically, the proximal ballooncontrol band 36 extends in the proximal direction beyond the proximalend of the balloon 28 and the distal balloon control band extends in thedistal direction beyond the distal end of the balloon 28. In addition,in FIG. 11, a gap is clearly seen between the distal end of the proximalballoon control band 36 and the proximal end of the stent S as well asbetween the proximal end of the distal balloon control band 24 and thedistal end of the stent S. This gap allows the stent S to be mounted onthe balloon 28 as the final step after the balloon angioplasty catheterhas been assembled. This differs from the embodiments taught by Fischellet al. in U.S. Pat. Nos. 6,375,660, 6,936,065 and 7,011,673 where theballoon control bands touch the stent without a gap. This would requirethat the balloon control bands be placed after the stent is mountedwhich is a much more difficult manufacturing process.

In some implementations, the balloon delivery apparatus includes acatheter comprising a proximal hypotube portion, a distal flexible tubeportion, and a lumen disposed longitudinally through the proximalhypotube portion and distal flexible tube portion. The balloon deliveryapparatus also includes a balloon having a proximal end that is affixedto a distal shaft mounting portion of the proximal hypotube portion anda distal end that is affixed to a core wire at a location proximal tothe distal tip of the core wire. The balloon can be coaxial with thecore wire and in fluid communication with the lumen of the proximalhypotube portion and the distal flexible tube portion. The balloondelivery apparatus includes a plurality of balloon control bands,wherein at least one balloon control band is located at the proximal endof the balloon and at least one balloon control band is located at thedistal end of the balloon. The balloon control bands may restrict theballoon's longitudinal expansion upon inflation.

In some examples, the proximal hypotube portion comprises a firstmaterial and the distal flexible tube section comprises a secondmaterial. For example, the proximal hypotube portion comprises a metal.In additional examples, the proximal hypotube portion comprisesstainless steel. And in some instances, the stainless steel is coatedwith PTFE. The proximal hypotube section may further include a pluralityof optical markers (e.g., depth markers). The distal flexible tubeportion may comprise a polymer material, which may comprise a siliconerubber material.

In some implementations, the distal tip of the core wire furthercomprises a prolate spherical or hemispherical cap. The core wirefurther comprises a coiled section wherein the coiled section is locatedproximal to the distal tip. The core wire may include a plurality ofdepth markers, wherein at least one depth marker is locatedapproximately concentrically with the proximal end of the balloon and atleast one depth marker is located approximately concentrically with thedistal end of the balloon. Optionally, the core wire includes at leastone protective tubular member having a length approximately equal to thelength of the balloon, wherein the protective tubular member is coaxialwith the core wire and the balloon. For example, the protective tubularmember can be disposed between the depth marker located approximatelyconcentrically with the proximal end of the balloon and the depth markercan be located approximately concentrically with the distal end of theballoon. In some examples, the balloon control bands comprise anelastomer material that elastically expands upon inflation of theballoon.

In some implementations, the balloon is a non-compliant ballooncomprising a polymer material. For instance, the balloon comprises apolyamide polymer material.

In some examples, the apparatus includes a handle affixed to theproximal hypotube portion. The handle may include an inflation controlthat controls the inflation of the balloon.

In some implementations, the balloon delivery catheter apparatusincludes a catheter comprising a proximal hypotube, a distal flexibletube, and a lumen that extends longitudinally throughout both tubes. Theballoon delivery catheter apparatus also includes a balloon near thedistal end of the proximal hypotube that fluidly communicates with thelumen. The balloon includes a distal end, a proximal end, and anintermediate segment. A core wire extending throughout at least aportion of the catheter lumen and beyond the distal end of the balloonincludes a proximal end, a distal tip, and a coiled member. The coiledmember can be disposed between the proximal end and the distal tip. Aproximal balloon control band may be concentrically arranged around theproximal end of the balloon, and a distal balloon control band may beconcentrically arranged about the distal end of the balloon. The distaland proximal balloon control bands may restrict inflation of the balloonat the proximal and distal ends of the balloon. The distal and proximalballoon control bands may comprise an elastomer material thatelastically expands during inflation of the balloon and contracts upondeflation.

In some examples, a bonding element coaxially mounted about the coiledmember of the core wire secures the distal end of the balloon to thecoil member.

A portion of the distal balloon control band may be affixed to thedistal end of the balloon. The proximal end of the balloon can beaffixed to the distal end the proximal hypotube, and the proximalballoon control band can be affixed to the proximal hypotube. Or, theproximal balloon control band can be affixed to the proximal end of theballoon. In additional examples, the proximal end of the core wire isaffixed to the distal end of the proximal hypotube.

In some examples, a plurality of depth markers are affixed to thecatheter (e.g., affixed to the proximal hypotube). Moreover, at leastone depth marker may be approximately concentric with the proximal endof the balloon and at least one depth marker may be approximatelyconcentric with the distal end of the balloon.

A protective tubing member, having a proximal end and a distal end, maybe affixed to the core wire so that the proximal end of the member isapproximately concentric with the proximal end of the balloon, and thedistal end of the member is approximately concentric with the distal endof the balloon.

In some implementations, the distal tip comprises a round surfacecomprising a hemisphere or prolate hemisphere. The balloon may comprisea polyamide polymer material (e.g., a polyamide material (e.g., Nylon)).

The proximal hypotube may comprise a first material and the distalflexible tube may comprise a second material. For example, the proximalhypotube may comprise stainless steel. In some instances, the stainlesssteel is substantially coated with a polymer material comprising PTFE.Moreover, the distal flexible tube may comprise a polymer materialcomprising silicone rubber.

Upon inflation, the balloon may adopt a geometry having two inwardfacing cones and a cylindrical segment located between said cones.

In some implementations, a handle may be connected to and in fluidcommunication with the lumen of the proximal hypotube. The handle mayinclude a docking torque apparatus having a base portion, a colletportion disposed within a passage of the base portion (208), and a headportion movably connected to the base portion. The head portion may beselectively engagable with the collet portion. The proximal shaftsection of the hypotube may be disposable through one or more of thehead portion, the collet portion, or the base portion. In some examples,the handle includes a strain relief member connected to the handle bodyand/or the base portion.

A method of treating vascular stenosis in a patient may includeproviding a balloon delivery apparatus that includes a handle having ahandle body, a catheter having a hypotube section, a distal shaftsection, and a lumen extending longitudinally throughout both sections.The hypotube section may be connected to the handle body, and the handlebody may be in fluid communication with the lumen. The balloon deliveryapparatus includes a balloon having a distal segment, an intermediatesegment, and a proximal segment, each of which is defined by an innersurface and an outer surface. The proximal segment of the balloon may beaffixed to the distal end of the hypotube section and in fluidcommunication with the lumen of the hypotube section. The balloondelivery apparatus includes a distal balloon control band having aninner surface, an outer surface, and a proximal end surface and aproximal balloon control band having an inner surface, an outer surfaceand a distal end surface. The inner surface of the distal ballooncontrol band is adjacent to the outer surface of the distal segment ofthe balloon. The inner surface of the proximal balloon control band isadjacent to the outer surface of the proximal segment of the balloonmember. A core wire extends through a portion of the distal shaftsection and entirely through the balloon. The handle slidably engagesthe hypotube section of the catheter, and rotational movement of thehandle longitudinally advances or retracts the core wire, the hypotubessection, the distal shaft section, or any combination thereof. Severalmethods further comprise inserting the balloon into a blood vessel of apatient. And some methods comprise advancing the balloon sufficientlyinto the vessel such that a portion of the intermediate segment of theballoon is approximately concentric with the stenosis. Some methodsfurther comprise inflating the balloon such that the stenosis is atleast partially alleviated. And, some methods further comprise deflatingthe balloon member and removing the balloon from the patient.

FIG. 15 provides a cross-section of a distal portion of a stent deliverycatheter 320. It would be typical of either an over-the-wire stentdelivery catheter or a rapid exchange stent delivery catheter to haveits distal portion to be formed as is shown in FIG. 15.

The stent delivery catheter 320 illustrated in FIG. 15 has an inner tube326 with an interior lumen 323 through which a guide wire 340 can beplaced. It would be typical of such a stent delivery catheter 320 to beadvanced over a guide wire 340 that would have been previously placedinto a blood vessel of the patient. The stent delivery catheter 320 alsohas an outer tube 324 which forms a doughnut shaped lumen 329 betweenthe inner surface of the outer tube 324 and the exterior surface of theinner tube 326. This doughnut (torroidal) shaped lumen 329 provides apassageway through which pressurized normal saline solution can be usedto inflate a balloon 325. The lumen 329 may also be used to deflate theballoon 325 after a stent 322 has been placed into a stenosis. The stentdelivery catheter 320 may include proximal and distal radiopaque markerbands 327, 328 that indicate under fluoroscopy the proximal and distalends of the stent 322.

In some implementations, the balloon 325 includes five sections whichare described (from its proximal end to its distal end) as follows:

1) A proximal cylindrical shaft 325A which is a cylindrical sectionfixedly joined to the outer tube 324.

2) A proximal conical section 325B attached at its proximal end to theproximal cylindrical shaft 325A and attached at its distal end to thecentral cylindrical section 325C of the balloon 325.

3) A central cylindrical section 325C attached at its proximal end tothe proximal conical section 325B and attached at its distal end to thedistal conical section 325D.

4) A distal conical section 325D attached at its proximal end to thecentral cylindrical section 325C and attached at its distal end to thedistal cylindrical shaft 325E.

5) A distal cylindrical shaft 325E attached at its proximal end to thedistal conical section 325D and fixedly joined to a distal portion ofthe inner tube 326.

Although the proximal conical section 325B is not clearly shown in FIG.15 to be of a conical shape, it can take that conical shape when theballoon 325 is inflated. Angioplasty balloons such as the balloon 325are typically made from a polymeric material such as nylon, formed intheir final desired shape and then folded or wrapped to thepre-deployment diameter shown in FIG. 15. It should be noted that theballoon 325 may be represented by as a single layer structure. Theballoon 325 can have several folds prior to inner tubular shaftinflation.

Also shown in FIG. 15 are a proximal balloon control band 332 and adistal balloon control band 334. Although the proximal balloon controlband 332 might extend in the proximal direction over only the proximalcylindrical shaft 325A of the balloon 325, it may extend over the outertube 324, creating a smooth transition from the outer tube 324 to thestent 322. Although the distal balloon control band 332 might extend inthe distal direction over only the distal cylindrical shaft 325A of theballoon 325, it may extend over the inner tube 324, creating a smoothtransition from the inner tube 324 to the stent 322. Smooth transitionsin a stent delivery catheter improve the deliverability of the stent intortuous vessels of the human body such as the coronary arteries. Theballoon control bands 332, 334 may be made from a highly elastic polymersuch as polyurethane or silicone rubber.

The balloon control bands 332, 334 may be used in conjunction with thestent 322 to prevent stent embolization or movement of the stent 322 offthe balloon in the proximal direction which can result in poordeployment. Specifically, the balloon control bands 332, 334, as shownin FIG. 15, can prevent embolization of any stent 322. Another importantfeature of the balloon control band 332 is that, in some examples, itextends proximal to the balloon proximal shaft 325A and has a taperedproximal end 333 that improves the stent delivery catheter's ability tobe easily pulled back into the guiding catheter through which it isplaced. The distal balloon control band 334 may extend distally beyondthe balloon distal shaft 325E and have a tapered distal end 335 forimproving the ability of the stent delivery catheter 320 to be pushedthrough a tight stenosis or though a tortuous arterial anatomy. Theoutside diameter of the distal balloon control band 334 may be equal toor greater than the diameter of the stent 322, creating a contour of theouter surface of the stent delivery catheter 320 which improves theability of the stent delivery catheter 320 to penetrate through a tightstenosis or navigate around a sharp bend.

The balloon control bands 332, 334 may assist with (1) refolding theballoon after it is inflated, (2) preventing bulging at the ends of theballoon during stent expansion (which is called “dog-boning,”) which cancause arterial restenosis, (3) providing a smooth tapered leading edgestent delivery system 320 so that the stent more easily can be pushedthrough a tight stenosis or around tight bends, (4) the distal ballooncontrol band can have an outside diameter that is greater than theoutside diameter of the stent 322 so that there is not a step up indiameter for the stent 322 as is the case for conventional balloonexpandable stent delivery systems, thus making it is easier to push thestent 322 through a tight stenosis; and (5) the interior edges of bothretention bands can keep the stent 322 positioned onto only the centralcylindrical section 325C of the balloon 325 so that the stent 322 staysover the central cylindrical section 325C of the balloon and is properlydeployed when the balloon 325 is inflated. Thus, the balloon controlbands 332 and 334 provide a multiplicity of advantages for the stentdelivery catheter 320. These same advantages of course apply to thestent-on-a-wire embodiments shown in FIGS. 2, 11 and 16.

As can be seen in FIG. 15, there should be a small distance G1 thatseparates the distal end of the proximal balloon control band 332 fromthe proximal end of the stent 322 and a distance G2 that separates theproximal end of the distal balloon control band from the distal end ofthe stent 322. This differs from the prior art by Fischell, et al, wherethe stent ends touch the edges of the balloon control bands. Each of thedistances G1 and G2 should be greater than 0.1 mm and less than 2.0 mm.The purpose of these distances G1 and G2 is to allow for uncertainly inmanufacturing for the actual length of the stents compared with theactual separation distance between the inner edges of the ballooncontrol bands 332 and 334. In addition, the distances G1 and G2 reducethe need for longitudinal positional accuracy as the stent 322 iscrimped down onto the balloon 325 in manufacturing the product. Similargaps between the balloon control bands and mounted stent are shown forthe stent-on-a-wire embodiment of FIGS. 11 and 16.

In the preferred embodiment of the present invention, the proximalballoon control band 332 is fixedly attached to the stent deliverysystem 320 proximal to the balloon proximal conical section 325B. Forexample, the proximal balloon control band 332 would be fixedly attachedto both the outer tube 324 and the balloon proximal cylindrical shaft325A but not attached to the balloon's proximal conical section 325B.During balloon inflation, this allows the balloon 325, including theproximal conical section 325B, to unfold and slide underneath theportion of the proximal balloon control band 332 that lies over theproximal conical section 325B of the balloon 325.

Similarly, the distal balloon control band 334 is fixedly attached tothe stent delivery system 320 distal to the balloon distal conicalsection 325D. For example, the distal balloon control band 334 would befixedly attached to both the inner tube 326 and the balloon distalcylindrical shaft 325E but not attached to the balloon distal conicalsection 325D. During balloon inflation, this allows the balloon 325including the distal conical section 325D to unfold and slide underneaththe portion of the distal balloon control band 334 that lies over thedistal conical section 325D of the balloon 325. These attachment methodsfor the balloon control bands 322 and 334 are also applicable to theballoon control bands 24 and 25 of FIG. 11.

Although the term “balloon control bands” has been used throughout thisdescription, an equally good name for these structures is “stentretention bands” as a major purpose of these elements is to preventstent embolization.

FIG. 16 is a cross-section of the distal portion of a stent-on-a-wireembodiment of the present invention which is a fixed wire stent deliverycatheter 420 which illustrates several novel features of the presentinvention.

The stent delivery catheter 420 illustrated in FIG. 16 has a core wire440 that extends into the distal tip 450 of the catheter 420. The stentdelivery catheter 420 also has an outer tube 424 which forms a doughnutshaped lumen 429 between the inner surface of the outer tube 424 and theexterior surface of the core wire 440. This doughnut (torroidal) shapedlumen provides the passageway through which pressurized normal salinesolution is typically used to inflate the balloon 425. The lumen 429 isalso used to deflate the balloon 425 after the stent 422 has been placedinto a stenosis. The stent delivery catheter 420 also has radiopaquemarker bands 427 and 428 that indicate under fluoroscopy the proximaland distal ends of the stent 422.

The balloon 425 has five sections which are described (from its proximalend to its distal end) as follows:

1) The proximal cylindrical shaft 425A which is a cylindrical sectionthat is fixedly joined to the outer tube 424.

2) The proximal conical section 425B that is attached at its proximalend to the proximal cylindrical shaft 425A and attached at its distalend to the central cylindrical section 425C of the balloon 425.

3) The central cylindrical section 425C that is attached at its proximalend to the proximal conical section 425B and attached at its distal endto the distal conical section 425D.

4) The distal conical section 425D that is attached at its proximal endto the central cylindrical section 425C and attached at its distal endto the distal cylindrical shaft 425E.

5) The distal cylindrical shaft 425E that is attached at its proximalend to the distal conical section 425D and is fixedly joined to theoutside of the distal tip 450.

Also shown in FIG. 16 are the proximal balloon control band 432 and thedistal balloon control band 434. Although the proximal balloon controlband 432 might extend in the proximal direction over only the proximalcylindrical shaft 425A of the balloon 425, in the preferred embodimentof the present invention, it extends over the outer tube 424 creating asmooth transition from the outer tube 424 to the stent 422. Although thedistal balloon control band 432 might extend in the distal directionover only the distal cylindrical shaft 425A of the balloon 425, in thepreferred embodiment of the present invention, it extends over the innertube 424 creating a smooth transition from the inner tube 424 to thestent 422. Smooth transitions in a stent delivery catheter will improvethe deliverability of the stent in tortuous vessels of the human bodysuch as the coronary arteries. The balloon control bands 432, 434 can bemade from a highly elastic polymer such as polyurethane or siliconerubber.

The balloon control bands 432, 434 may be used in conjunction with thestent 422 to prevent stent embolization or movement of the stent 422 offthe balloon 425 in the proximal direction which can result in poordeployment. For example, the balloon control bands 432, 434, examples ofwhich are shown in FIG. 16, may prevent embolization of any stent 422.The proximal balloon control band 432 may extend proximal to the balloonproximal shaft 425A and have a tapered proximal end that improves stentdelivery catheter's ability to be easily pulled back into the guidingcatheter through which it is placed. The distal balloon control band 434may extend distally beyond the balloon distal shaft 425E and have atapered distal end that improves the ability of the stent deliverycatheter 420 to be pushed through a tight stenosis. The outside diameterof the distal balloon control band 434 may be equal to or greater thanthe outside diameter of the stent 422, creating a contour for the outersurface of the stent delivery catheter 420 that improves the ability ofthe stent delivery catheter 420 to penetrate through a tight stenosis ornavigate around a sharp bend.

The balloon control bands 432, 434 may aid (1) refolding the balloonafter it is inflated, (2) preventing bulging at the ends of the balloonduring stent expansion (which is called “dog-boning”), which can causearterial restenosis, (3) providing a smooth tapered leading edge stentdelivery system 420 so that the stent 422 can be more easily pushedthrough a tight stenosis or around tight bends, (4) making it is easierto push the stent 422 through a tight stenosis, as by having an outsidediameter of the distal balloon control band that is greater than theoutside diameter of the stent 422 so that there is not a step up indiameter for the stent 422 as is the case for conventional balloonexpandable stent delivery systems; and (5) keeping the stent 422positioned onto only the central cylindrical section 425C of the balloon425 using the interior edges of both balloon control bands 432, 434 sothat the stent 422 stays over that central cylindrical section 425C ofthe balloon and is properly deployed when the balloon 425 is inflated.

As can be seen in FIG. 16, a small distance G3 may separate the distalend of the proximal balloon control band 432 from the proximal end ofthe stent 422 and a distance G4 may separate the proximal end of thedistal balloon control band from the distal end of the stent 422. Thisdiffers from the prior art by the Fischell patents (noted earlier),where the stent ends touch the edges of the balloon control bands. Insome implementations, each of the distances G3, G4 are greater than 0.1mm and less than 2.0 mm. These distances G3, G4 may allow foruncertainly in manufacturing for the actual length of the stentscompared with the actual separation distance between the inner edges ofthe balloon control bands 432, 434. In addition, the distances G3, G4may reduce the need for longitudinal positional accuracy as the stent422 is crimped down onto the balloon 425 in manufacturing the product.Similar gaps between the balloon control bands 432, 434 and mountedstent are shown for the stent-on-a-wire implementation shown in FIG. 11and the implementation shown in FIG. 15 that is adapted to be advancedover a guide wire.

In some implementations, the distal tip 450 of the catheter 420 has acentral wire 445 that connects to the core wire 440. The proximal end ofthe distal tip 450 may have a plastic sleeve 441 covering the centralwire 445 so that the distal cylindrical shaft 425E of the balloon 425can be more easily attached to the distal tip 450. The central portionof the distal tip 450 may have a helical wire 444 wrapped around thecentral wire 445. The distal portion of the distal tip 450 may have anend piece 446 attached to the distal end of the central wire 445. Alubricity coating 442 may cover the outer surface of the distal tip 450.It is also envisioned that a lubricity coating may cover the entireouter surface of the catheter 420 except for the balloon 425 and stent422.

In some implementations, the proximal balloon control band 432 isfixedly attached to the stent delivery system 420 proximal to theballoon proximal conical section 425B. For example, the proximal ballooncontrol band 432 can be fixedly attached to both the outer tube 424 andthe balloon proximal cylindrical shaft 425A, but not attached to theballoon's proximal conical section 425B. During balloon inflation, thisallows the balloon 425, including the proximal conical section 425B, tounfold and slide underneath the portion of the proximal balloon controlband 432 that lies over the proximal conical section 425B of the balloon425. The distal balloon control band 434 can be fixedly attached to thestent delivery system 420 distal to the balloon distal conical section425D. For example, the distal balloon control band 434 can be fixedlyattached to both the plastic sleeve 441 and the balloon distalcylindrical shaft 425E, but not attached to the balloon distal conicalsection 425D. During balloon inflation, this allows the balloon 425including the distal conical section 425D to unfold and slide underneaththe portion of the distal balloon control band 434 that lies over thedistal conical section 425D of the balloon 325.

In some implementations, a stent delivery catheter 320, 420 includes acatheter tubing 324, 424 defining a lumen therethrough, a balloon 325,425 disposed near a distal end of the catheter tubing 324, 424 andmoving between deflated and inflated states, and proximal and distalballoon control bands 332, 334, 432, 434 concentrically arranged arounda respective proximal end portion (e.g., a proximal cylindrical shaft325A, 425A and/or a proximal conical section 325B, 425B) and arespective distal end portion (e.g., a distal conical section 325D, 425Dand/or a distal cylindrical shaft 325E, 425E) of the balloon 325. Theproximal balloon control band 332, 334 has a proximal end locatedproximally of a proximal end of the balloon 325 and a distal end locatedadjacent a proximal end of a received unexpanded stent 322, 422. Thedistal balloon control band 334, 434 has a proximal end located adjacenta distal end of the received unexpanded stent 322, 422 and a distal endlocated distally of a distal end of the balloon 325, 425. The ballooncontrol bands 332, 334, 432, 434 may each have a diametric cross-sectionlarger than the balloon 325, 425 in an uninflated state and theunexpanded stent 322, 422 received over the balloon 325, 425 to impedeaxial movement of the unexpanded stent 322, 422 off of the balloon 325,425.

In some implementations, each balloon control band 332, 334, 432, 434comprises an elastic material that expands during inflation of theballoon 325, 425 and contracts upon deflation of the balloon 325, 425.The proximal and distal balloon control bands 332, 334 may be secured tothe respective proximal and distal end portions of the balloon 325, 425.Moreover, the proximal end portion of the balloon 325, 425 and theproximal balloon control band 332, 432 can both be attached to thecatheter tubing 324, 424. In some examples, the proximal balloon controlband 332, 432 is attached at least partially to the balloon 325, 425 andat least partially to the catheter tubing 324, 424. In additionalexamples, the distal balloon control band 334, 434 is attached at leastpartially to the balloon 325, 425 and at least partially to a core wire445. Each balloon control band 332, 334, 432, 434 may have a non-uniformcross-sectional thickness ΔD along an axial direction of the ballooncontrol band. In some implementations, each balloon control band 332,334, 432, 434 has first and second end portions. The first end portionmay have a larger diametric cross-section DC_(A) than the second endportion. Moreover, the first end portion of each balloon control band332, 334, 432, 434 may be disposed adjacent to a received stent on theballoon.

In some implementations, a method of manufacturing a medical deviceincludes disposing a balloon 325, 425 near a distal end of a cathetertubing 324, 424. The balloon 325, 425 is movable between deflated andinflated states. The method further includes disposing an unexpandedstent 322, 422 over the balloon 325, 425 in an uninflated state,arranging a proximal balloon control band 332, 432 concentrically arounda proximal end portion of the balloon 325, 425 (e.g., a proximalcylindrical shaft 325A, 425A and/or a proximal conical section 325B,425B), and arranging a distal balloon control band 334, 434concentrically around a distal end portion of the balloon 325, 425(e.g., a distal conical section 325D, 425D and/or a distal cylindricalshaft 325E, 425E). The proximal balloon control band 332, 432 has aproximal end located proximally of a proximal end of the balloon 325,425 and a distal end located adjacent a proximal end of the unexpandedstent 322, 422. The distal balloon control band 334, 434 has a proximalend located adjacent a distal end of the unexpanded stent 322, 422 and adistal end located distally of a distal end of the balloon 325, 425. Theballoon control bands 332, 334, 432, 434 may each have a diametriccross-section larger than the balloon 325, 425 in an uninflated stateand the unexpanded stent 322, 422 received over the balloon 325, 425 toimpede axial movement of the unexpanded stent off of the balloon.

In some implementations, each balloon control band 332, 334, 432, 434comprises an elastic material that expands during inflation of theballoon 325, 425 and contracts upon deflation of the balloon. The methodmay include at least partially securing the proximal and distal ballooncontrol bands 332, 334, 432, 434 to the respective proximal and distalend portions of the balloon 325, 425. In some examples, the methodincludes affixing the proximal end portion of the balloon 325, 425 andthe proximal balloon control band 332, 432 both to the catheter tubing324, 424. In additional examples, the method includes shaping theballoon control bands 332, 334, 432, 434 to have a non-uniformcross-sectional thickness along an axial direction of the ballooncontrol bands. Each balloon control band 332, 334, 432, 434 has firstand second end portions. The first end portion may have a largerdiametric cross-section than the second end portion. The method mayinclude arranging the first end portion of each balloon control band332, 334, 432, 434 adjacent to a received stent 322, 422 on the balloon325, 425.

In some implementations, a method of treating vascular stenosis includesinserting into a vessel of a patient a portion of a stent deliverycatheter 320, 420. The stent delivery catheter 320, 420 includes acatheter tubing 324, 424 defining a lumen therethrough, a balloon 325,425 disposed near a distal end of the catheter tubing 324, 424 andmoving between deflated and inflated states, and proximal and distalballoon control bands 332, 334, 432, 434 concentrically arranged arounda respective proximal end portion (e.g., a proximal cylindrical shaft325A, 425A and/or a proximal conical section 325B, 425B) and arespective distal end portion (e.g., a distal conical section 325D, 425Dand/or a distal cylindrical shaft 325E, 425E) of the balloon 325. Theproximal balloon control band 332, 334 has a proximal end locatedproximally of a proximal end of the balloon 325 and a distal end locatedadjacent a proximal end of a received unexpanded stent 322, 422. Thedistal balloon control band 334, 434 has a proximal end located adjacenta distal end of the received unexpanded stent 322, 422 and a distal endlocated distally of a distal end of the balloon 325, 425. The ballooncontrol bands 332, 334, 432, 434 may each have a diametric cross-sectionlarger than the balloon 325, 425 in an uninflated state and theunexpanded stent 322, 422 received over the balloon 325, 425 to impedeaxial movement of the unexpanded stent 322, 422 off of the balloon 325,425. The method includes advancing the balloon across the vascularstenosis, inflating the balloon to compress the vascular stenosis,deflating the balloon, and removing the stent delivery catheter from thepatient.

In some implementations, a balloon angioplasty catheter 320, 420includes a catheter tubing 324, 424 defining a lumen therethrough, andan inflatable balloon 325, 425 having a central cylindrical portion325C, 425C, a distal portion having a distal conical portion 325D, 425Dand a distal cylindrical shaft 325E, 425E, and a proximal portion havinga proximal conical portion 325B, 425B and a proximal cylindrical shaft325A, 425A. The proximal shaft 325A, 425A of the inflatable balloon 325,425 can be fixedly attached to a distal end of the catheter tubing 324,424. A balloon control band 334, 434 is mounted coaxially over thedistal portion of the inflatable balloon 325, 425. The balloon controlband 334, 434 extends in a distal direction beyond the distal shaft325E, 425E of the inflatable balloon 325, 425 and has a proximal endlocated near a proximal end of the distal conical section 325D, 425D ofthe balloon 325, 425 when the balloon is in an uninflated state. In thisconfiguration, a proximal balloon control band 332, 432 is notnecessarily needed or used.

In some implementations, the balloon angioplasty catheter 320, 420includes a balloon expandable stent 322, 422 having a proximal end and adistal end. The stent 322, 422 is mounted coaxially onto the centralcylindrical section 325C, 425C of the inflatable balloon 325, 425 withthe distal end of the stent 322, 422 adjacent the proximal end of theballoon control band 334, 434. In some examples, a separation distanceG2, G4 between the distal end of the stent 322, 422 and the proximal endof the balloon control band 334, 434 is less than about 2 mm. Theballoon angioplasty catheter 320, 420 may include a fixed guide wire440, 445 extending in a distal direction beyond the distal end of thedistal balloon shaft 325E, 425E. In some examples, the balloon controlband 334, 434 has a diametric cross-section larger than the balloon 325,425 in an uninflated state and an unexpanded stent 322, 422 receivedover the balloon 325, 425 to impede axial movement of the unexpandedstent 322, 422 off of the balloon 325, 425. For example, a maximum outerdiameter of the balloon control band 334, 434 may be within 1.0 mil ofan outside diameter of an unexpanded stent 322, 422 received by theballoon 325, 425. Moreover, a maximum outer diameter of the ballooncontrol band 334, 434 can be between 1.0 mil and 3.0 mils greater thanan outer diameter of an unexpanded stent 322, 422 received by theballoon 325, 425.

A number of implementations have been described. Nevertheless, it willbe understood that various modifications may be made without departingfrom the spirit and scope of the disclosure. Accordingly, otherimplementations are within the scope of the following claims.

What is claimed is:
 1. A balloon delivery catheter apparatus comprising:a catheter tubing defining a lumen therethrough and having proximal anddistal ends; a balloon disposed near a distal end of the catheter tubingand moving between deflated and inflated states; a core wire having aproximal end attached to the catheter tubing inside the lumen andextending distally away and substantially co-axially with the cathetertubing through the balloon to a distal free end; proximal and distalballoon control bands concentrically arranged around respective proximaland distal end portions of the balloon, each balloon control bandcomprising an elastic material that expands during inflation of theballoon and contracts upon deflation of the balloon, the balloon controlbands impeding expansion of the proximal and distal end portions of theballoon and assisting deflation of the balloon after balloon inflation,wherein the balloon control bands each have a diametric cross-sectionlarger than the balloon in its uninflated state and an unexpanded stentreceived over the balloon to impede axial movement of the unexpandedstent off of the balloon; a coil disposed around the core wire, the coilhaving a proximal end attached to at least one of the distal end portionof the balloon and the distal balloon control band; and a handlereceived by the proximal end of the catheter tubing, the handlecomprising: a handle base defining a handle lumen therethrough; a colletreceived at least partially in the handle lumen at a distal end portionof the handle base, the collet defining a collet lumen therethrough; anda handle head releasably connected to the distal end portion of thehandle base over the collet, the handle head defining an apertureaxially aligned with the collet lumen and sized to receive the proximalend of the catheter tubing therethrough and at least partially in thecollet lumen, wherein the handle lumen is in fluid communication withthe lumen of the received catheter tubing, and wherein movement of thehandle head toward the handle base causes constriction of the colletabout the received catheter tubing.
 2. The balloon delivery catheterapparatus of claim 1, wherein the proximal and distal balloon controlbands are secured to the respective proximal and distal end portions ofthe balloon.
 3. The balloon delivery catheter apparatus of claim 1,wherein the proximal end portion of the balloon and the proximal ballooncontrol band are both attached to the catheter tubing.
 4. The balloondelivery catheter apparatus of claim 3, wherein the proximal ballooncontrol band is attached at least partially to the balloon and at leastpartially to the catheter tubing.
 5. The balloon delivery catheterapparatus of claim 1, wherein the distal balloon control band isattached at least partially to the balloon and at least partially to thecore wire.
 6. The balloon delivery catheter apparatus of claim 1,wherein each balloon control band has a non-uniform cross-sectionalthickness along an axial direction of the balloon control band.
 7. Theballoon delivery catheter apparatus of claim 6, wherein each ballooncontrol band has first and second end portions, the first end portionhaving a larger diametric cross-section than the second end portion, thefirst end portion of each balloon control band disposed adjacent to areceived stent on the balloon.
 8. The balloon delivery catheterapparatus of claim 1, wherein the balloon and the balloon control bandsare coaxially disposed about the core wire.
 9. The balloon deliverycatheter apparatus of claim 1, wherein the coil extends beyond thedistal end portion of the balloon.
 10. The balloon delivery catheterapparatus of claim 1, wherein the balloon control bands restrictexpansion of at least the end portions of the balloon to a thresholddiameter.
 11. The balloon delivery catheter apparatus of claim 1,wherein the collet comprises: a substantially tubular section having anouter diameter less than or equal to a diameter of the handle lumen; anda chuck attached to the substantially tubular section and having anouter diameter larger than the handle lumen, the chuck defining achamfered surface arranged to engage an opposing chamfered surface ofthe handle base; wherein movement of the handle head toward the handlebase causes movement of the collet toward the handle base and thechamfered surface of the handle base to exert a substantially radiallyinward force on the opposing chamfered surface of the chuck.
 12. Theballoon delivery catheter apparatus of claim 1, wherein the handle headis threadably received by the distal end portion of the handle base. 13.The balloon delivery catheter apparatus of claim 1, wherein the handlefurther comprises a valve member disposed on a proximal end portion ofthe handle base.
 14. The balloon delivery catheter apparatus of claim 1,wherein the handle further comprises a strain relief disposed on atleast one of the handle base and the handle head.
 15. A balloon deliverycatheter apparatus comprising: a catheter tubing defining a lumentherethrough and having proximal and distal ends; a balloon disposednear a distal end of the catheter tubing and moving between deflated andinflated states, the balloon having a proximal end portion and a distalend portion; a core wire having a proximal end attached near the distalend of the catheter tubing inside the lumen and extending distally awayand substantially co-axially with the catheter tubing through theballoon to a distal free end; a coil disposed around the core wire, thecoil having a proximal end attached to the distal end portion of theballoon; a balloon support tube co-axially disposed over the core wireand within the balloon, wherein the balloon support tube preventscompression of the balloon below a threshold diameter; and a handlereceived by the proximal end of the catheter tubing, the handlecomprising: a handle base defining a handle lumen therethrough; a colletreceived at least partially in the handle lumen at a distal end portionof the handle base, the collet defining a collet lumen therethrough; anda handle head releasably connected to the distal end portion of thehandle base over the collet, the handle head defining an apertureaxially aligned with the collet lumen and sized to receive the proximalend of the catheter tubing therethrough and at least partially in thecollet lumen, wherein the handle lumen is in fluid communication withthe lumen of the received catheter tubing, and wherein movement of thehandle head toward the handle base causes constriction of the colletabout the received catheter tubing.
 16. The balloon delivery catheterapparatus of claim 15, wherein the balloon support tube preventscompression of a received stent over the balloon to a diameter less thana threshold un-deployed stent diameter.
 17. The balloon deliverycatheter apparatus of claim 15, wherein the balloon support tube has anaxial length less than or equal to an axial length of the balloon. 18.The balloon delivery catheter apparatus of claim 15, wherein the balloonsupport tube is attached to the core wire so that a proximal end of theballoon support tube is approximately concentric with a proximal end ofthe balloon, and a distal end of the balloon support tube isapproximately concentric with a distal end of the balloon.
 19. Theballoon delivery catheter apparatus of claim 15, wherein the balloonsupport tube comprises a polyamide material.